Abstract
Purpose
We compare the Soft Seal™ and Unique™ single-use, plastic laryngeal mask airway devices with respect to intracuff pressure, directly measured mucosal pressure andin vitro elastance.
Methods
Ten fresh male cadavers were studied. Microchip pressure sensors were attached to the following locations: A) the anterior middle part of the cuff side; B) the posterior tip of the cuff; C) the anterior base of the cuff; D) the posterior middle part of the cuff side; E) the backplate; and F) the posterior tube. The size 5 Unique™ and size 5 Soft Seal™ were inserted in random order using laryngoscope-guidance. Intracuff pressure and mucosal pressure were documented at 0 to 40 mL cuff volume in 10 mL increments.In vitro elastance was determined between 20 to 40 mL cuff volume.
Results
For both devices, mucosal pressure increased with cuff volume at most locations. Intracuff pressures andin vitro elastance (5.2 ± 0.7 cm H2O/mLvs 3.8 ± 0.4 cm H2O/mL,P < 0.0001) were higher for the Unique™ than the Soft Seal™ (P < 0.0001), but there were no differences in mucosal pressures at any location or cuff volume.
Conclusion
Intracuff pressures andin vitro elastance are higher for the Unique™ than the Soft Seal™, but mucosal pressures are similar suggesting that the airway morbidity will be similar.
Résumé
Objectif
Nous comparons deux masques laryngés jetables en plastique, Soft Seal™ et Unique™, quant à la pression intraballonnet, la pression sur la muqueuse mesurée directement et l’élastance in vitro. Méthode : Notre expérience a porté sur dix cadavres mâles. Des microdétecteurs de pression ont été fixés sur A) la partie latérale médiane antérieure du ballonnet;B) la pointe postérieure du ballonnet;C la base antérieure;D la partie médiane postérieure;E la lame dorsale et F) le tube postérieur. Les masques de grandeur 5 Unique™ et Soft Seal™ ont été insérés selon un ordre aléatoire à l’aide d’un laryngoscope. La pression intraballonnet et la pression sur la muqueuse ont été vérifiées pour des volumes de ballonnet de 0 à 40 mL en paliers de 10 mL. L’élastance in vitro a été déterminée pour un volume de 20 à 40 mL.
Résultats
La pression sur la muqueuse augmentait avec le volume du ballonnet pour la majorité des points de mesure et chacun des appareils. Les pressions intraballonnet et l’élastance in vitro (5,2 ±0,7cm H2O/mL vs 3,8 ± 0,4 cm H2O/mL, P < 0,0001 ) étaient plus élevées avec le masque Unique™ qu’avec le Soft Seal™ (P < 0,0001), mais les pressions sur la muqueuse ne présentaient aucune différence pour tous les points de mesure et tous les volumes du ballonnet.
Conclusion
Les pressions intraballonnet et l’élastance in vitro sont plus élevées avec le masque Unique™ qu’avec le Soft Seal™, mais les pressions sur la muqueuse sont similaires, ce qui laisse croire que la morbidité d’une telle canulation sera similaire.
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Disclosure: Dr. Brimacombe and Dr. Keller have previously worked as consultants for the Laryngeal Mask Company. This study was supported solely by departmental funds.
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Keller, C., Brimacombe, J., Moriggl, B. et al. In cadavers, directly measured mucosal pressures are similar for the Unique™ and the Soft Seal™ laryngeal mask airway devices. Can J Anesth 51, 834–837 (2004). https://doi.org/10.1007/BF03018460
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DOI: https://doi.org/10.1007/BF03018460